Apparatus for closing the edges of packages



Sept. 18, 1962 T. l.. HARRISON ETAL 3,054,242

APPARATUS FOR CLOSING THE EDGES OF PACKAGES 5 Sheets-Sheet l Filed March 9, 1960 lli ,.,l\\u\ l l H n||| E MMINHJ MMWWW; W\|.N v E! @v E m. N S @Q wf Sept. 18, 1962 T. l.. HARRISON ETAL APPARATUS FoP CLOSING THE EDGEs oF PACKAGES 5 Sheets-Sheet 2 Filed March 9, 1960 Sept 18, 1962 T. l.. HARRISON ETAL 3,054,242

APPARATUS FOR CLOSING THE EDGES OF' PACKAGES Filed March 9, 1960 3 Sheets-Sheet 5 BY Mw (M01 gilet" 3,054,242 APPARATUS FOR CLOSING 'IHE EDGES 0F PACKAGES Thomas L. Harrison, Menomonee Falls, and Robert H.

Pratt, Milwaukee Wis., assignors to Pratt Manufacturing Corp, a corporation of Wisconsin Filed Mar. 9, 1960, Ser. No. 13,869 14 Claims. (Cl. 53-378) This invention relates to apparatus for closing the edges of packages.

In the manufacture of fiat packages from super-imposed sheets of paper or the like the closing and sealing of the edges of such packages has presented a problem. Packages of this type are frequently employed for sterile articles such as gauze pads, dressings, sponges and other surgical supplies. These packages must be neat and attractive in appearance and must be capable of being formed rapidly on production machinery. It is quite common on packages of this type to employ double-folds at the edges in order to close and seal said edges. These folds are commonly called drug folds.

Heretofore a side folding member having a generated curve therein was used to form the first fold and the fold was then pressed down by a roller and then a second member having another generated curve was used to form the second fold and there had t be a second pressing operation to crease the folds. This apparatus was expensive to manufacture as the folding member had to be produced on an expensive cutting machine and had to be rotated while it was `being cut to generate the curvature. In aldition, the prior structure did not in itself do the creasing inasmuch as separate rollers had to be provided for this work after both the irst and second folds.

Itis a general object of the present invention to provide approved apparatus for making drug folds at the edges of packages, which apparatus can be produced by straight line lcutting methods and which eliminates the necessity of utilizing an intermediate pressing roller to press the first fold, the apparatus having its own stationary creasing mechanism embodied therein whereby a drug fold is produced with apparatus which is much less expensive.

It is a further object of the present invention to provide improved means for quickly and expeditiously forming drug folds and for securing the same in folded position.

A further object of the invention is to provide a device as above described which permits rapid formation of drug folds on packages while the latter are being conveyed rapidly in line formation.

A still further object of the invention is to provide mechanism as above described wherein the folding in strumentalities have no moving parts and therefore cannot get out of order.

With the above and other objects in view the invention consists of the improved apparatus for closing the edges of packages, and all its parts and combinations, as set forth in the claims, and all equivalents thereof.

In the accompanying drawings, illustrating one com plete embodiment of the preferred form of the invention, in which the same reference numerals designate the same parts in all of the views:

FIG. l is a top View of the improved apparatus, parts being broken away and shown in section, and the ends of the conveyor being broken olf;

FIG. 2 is a fragmentary sectional view taken on the line 2-2 of FIG. l showing ythe iirst stage in the production of a drug fold in one side of a package;

FIG. 3 is a sectional view taken on the line 33 of FIG. l showing a second stage wherein the upwardly flanged part of FIG. 2 has been folded down into parallelism with the top of the package;

FIG. 4 is a sectional view taken on the line #LA of FIG. l showing the next stage where the doubled over edge portion is folded up at right angles;

FIG. 5 is a sectional view taken on the line 5 5 of FIG. 1 showing how the upwardly flanged double portion of FIG. 4 is again folded down in-to parallelism;

FIG. 6 is a sectional view taken on the line 6 6 of FIG. 1 showing the final pressing of the drug fold in place;

FIG. 7 is a sectional view taken on line 7-7 of FIG. 2 with the package omitted;

FIG. 8 is a sectional view taken on line SaS of FIG. 3 with the package omitted;

FlG. 9 is a View looking at the inner side of one of the folding rails, the view being taken approximately on the line 9-9 of FIG. 1;

FIG. 10 is a perspective View of the initial guiding member on one side of the'device (the lower side of FIG. l);

FIG. 11 is a view of the underside of the first fold- 'down member (being the one on the upper side of FIG. 1);

FIG. 12 is a top View of an intermediate up-ilanging member with the cover plate removed (being the one shown on theupper side of FIG. l);

FIG. 13 is a side view of the member of FIG. l2;

FIG. 14 is a perspective View of one of the curved guides for the final down-fold (being the one shown on the bottom of FIG. 1);

FIG. l5 is a fragmentary elevational view showing the mechanism for applying glue; and

FIG. 16 is a transverse sectional View through one of the flushed packages.

Referring more particularly tothe drawings, the device includes a suitably driven endless best 20 on which two superimposed sheets of paper or similar material are being conveyed through the folding mechanism to lhave both side edges simultaneously closed with drug folds. The sheets of paper are held down on the belt by suitable hold-down rollers 21, as is common in the industry. The pair of sheets may be the top 22 and bottom 23 of a package P for holding a flat article such as a surgical sponge 24 (see FIG. 16), it being the function of this machine to make the drug folds 25 in the edges thereof and to seal said folds in folded position with the article in the package. Y Y

Referring again to FIG-1, the dot and dash lines P indicate apackage entering the folding apparatus and P', another package leaving; the packages entering the apparatus in suitably spaced line formation approximately as illustrated in FIG. 1. f

Suitably supported on eachrside of the traveling belt 20' are stationary folding members 26, the members on the two sides being the same except that one is a right and the other is a left In the description which follows, only one of these folding members 26 will be described and the same reference numerals will be used on the two sides ofthe machine to indicate corresponding parts. Each folding `member has a base portion 27 formed of a flat piece of metal of the thickness shown in FIG. 9. Bolted on top of the base member at the entrance end of the folding member is an initial anger comprising the part 28 in conjunction with a guide member 29. he member 28 has been shown in FIGS. 1, 2 and 7. It is generally L-shaped in cross-section as shown in FIG. 2, to provide a shoulder portion 30', and a longitudinally extending inclined surface 31 which commences at the level of the top surface of the base 27 -and inclines up to the height shown in` FIG; 2.- The inclined surface 31 has an outside shoulder 32 which is of progressively increasing height as shown in FIG. 7.

The guide member 29 includes an upright outer Wall 33 from the lower edge of which a thin guiding strip 34 projects inwardly terminating close to the shoulder 32, as shown in FIG. 2 (see also FIG. 10). The strip 34 is curved at the entrance end as at 35. Thereafter, it is straight and horizontal and spaced a uniformly small distance above the top of the base 27, this spacing just being sufficient to accommodate the layers of paper below the strip 34. The guide member 29 has mounting lugs -36 which are detachably connected in position by bolts 37 so that the guide member is supported on top of the member 28 (as well as on top of the down-fold member next to be described).

As the result of this structure, when the package P first enters beneath the curved portions 35 of the strips 34 of the members 29, the edges of the package will thereafter be guided in flat condition onto the inclined planes 31. However, these portions of the package cannot travel up the inclines 31 because they are held down on the base by the guiding strips 34. As a result, the edges are flanged upwardly as at F (FIG. 2) against the shoulders 32 of progressively increasing height. Thus, Iby the time all portions of the package have passed the members 28, the superimposed package edges are flanged upwardly at right angles against the shoulders 32 with the free edges of the strips 34 at the fold line.

While still held down by the strips 34, the package P continues and each flange F is engaged by a down-folder 38. The underside of one of these downfolders is shown in FIG. l1 and it will be seen that there is an overhang 39 of gradually increasing width which overhangs a longitudinal shoulder 40. As the package flange F passes against the leading portion 41 of the shoulder 40, it is guided by the incline 42 (FIG. ll and FIG. l) in a laterally inward direction which causes it to fold around the free edge of the strip 34 and to be gradually transferred to a attened down condition below the overhang 39 in the groove 43 of FIG. 3. This is due to the fact that the flange F has no other place to go but to fold over and to be accommodated in the groove 43, its fully folded down position being shown in FIG. 3. At approximately the position of FIG. 3, the guiding strip 34 ends as shown in FIG. 8. Just beyond this point the edge of the base is slotted on an incline as at 44, and a band spring 45, which has its lower end secured to the bottom of the base as at 46, has its upper end pressing resiliently against the underside of the overhang 39. Thus, as soon as the package portion leaves the end of the strip 34 the spring presses the folded portion against the underside of the shoulder 39 and creases it as is clear from FIG. 8.

Thereafter, the package is acted upon by a second flanger 47, a top view of this flanger with its cover removed being shown in FIG. 12 and a side view being shown in FIG. 13. The folded-down edge portion of the package first passes onto the inclined plane 48 of the member 47, which inclined plane is of progressively increasing width as shown in FIG. 12. A hold down member 49 (FIG. 1) which is bolted down on top of the member 47 as shown in FIG. l, carries a depending flange 49' (see FIG. 4). This flange tends to hold the package down on the base portion 27 so that as it tries to travel up the inclined plane 48 it is gradually transferred to a position against the side shoulder 50. This causes the previously doubled down portion to be flanged upwardly to the position shown at F2 in FIG. 4.

As the package is moving along this second flanger 47 it is engaged by a glue depositing segment 51, the operation of which will be hereinafter described, so that there is a strip of adhesive deposited on the package at the location shown in FIG. 4 preparatory to the ange portions F2 being flattened down on top of the adhesive.

Referring next particularly to FIG. 5, it will be seen that there is another downfolder 52 secured on top of the base which is practically the same as the member 38 shown in FIG. 3 and in FIG. l1. 'I'he member 52 of FIG. has an overhang 53 of gradually increasing width as is shown in FIG. l, and beneath said overhang is a longitudinal-vertical shoulder portion 54. Bolted on top of the member 52 is a support 55 to which a paper guiding blade 56 is secured as at 57. The opposite blade from the one shown in FIG. 5 is illustrated in perspective in FIG. 14 and it will be seen that it is a thin strip of material which extends vertically downwardly and which has a rolled portion of gradually increasing width merging into a substantially horizontal portion 57, that is, the lead end of the rolled portion practically merges with the vertical portion at 58 and it then gradually increases in Width to the maximum width shown in FIG. 5. The horizontal fold-defining blade portion 57 is supported midway of the depth of the groove 59 of FIG. 5 so that the sheet material beneath it will be held down on the base while there is still room for the flanged portions to fold around the free edge 60.

Wth this arrangement, as the package moves along, the upstanding flange F2 of FIG. 4 will be first accommodated between the vertical portion of the blade 56 and a vertical side portion (61 FIG. l) of the block 52 which corresponds to the lead part 41 of FIG. 11, and which is ahead of the beginning of the overhang 53. Thereafter as the overhang 53 of gradually increasing width is approached, the overhang will cause the upwardly flanged portions F2 to fold down and be transferred to a position beneath the overhang and on top of the blade portion 57 as shown in FIG. 5 to thus substantially complete the drug fold. Thereafter, the package passes beyond the tip 62 of the blade and beneath the overhang 63 of a pressing member 64 as shown in FIG. 6, which member further presses the parts in folded position against the strip of adhesive which has been previously applied. This completes the operation, but if desired, the package leaving the members 64 may be additionally engaged by final creasing rollers (not shown). The package emerges from the apparatus in the condition shown in FIG. 16 with the drug folds 25 held in folded condition by the adhesive strips 65 thereby sealing the edges of Ithe package.

Referring now to FIG. 15, there is suitably supported above the apparatus of FIG. 1 a pan 66 containing an adhesive in liquid form. Supported for rotation on bearings 67 above the pan so that its lower periphery rotates therein is an adhesive pick-up roll 68 which is engaged at intervals by the adhesive applicator segment 50 having the arcuate applicator edge 69. The latter is mounted on a suitably journaled shaft 70. Carried by the shaft 70 at one end is a sprocket wheel 71 driven by an endless chain 72 from a suitable source of power. The operation of the adhesive applying segment 69 is so timed as to engage a package as in FIG. 4 whenever a package is in the position of FIG. 4 and just before the upwardly flanged parts F2 are folded down. Preferably the base member 27 has slots 73 below the point of glue application to allow drainage of any surplus glue in case the device is run when there are no packages therein. There are, of course, two of the glue applying segments 50 in the apparatus of FIG. 1--one for each side.

I-t is apparent from the above that the top and bottom sheets of the packages, with the item 24 therebetween, may be fed rapidly in line formation through the apparatus to have both ends simultaneously closed and sealed by means of drug folds which are maintained in folded condition by an adhesive. It is obvious that the instrumentality of FIG. 1 may be used either in the double form shown or singly where it is only necessary to have a drug fold on one edge.

It is apparent from FIGS. 2 to 6 that the members 28, 38, 47, 52 and 64 may be easily formed by simple milling operations and detachably bolted to a base strip, and .that the cooperating members 33-34, 42 and `56 may be also easily formed from sheet material and suitably secured to the top supports to depend therefrom. The curvatures 57 on the blades 56 may be easily formed on the relatively thin stock necessary for this part. It is also apparent that the assembly of these parts is simple and that the resulting apparatus is foolproof because of the fact that the edgefolding members shown in FIGS. 2 to 6, inclusive, have no moving parts.

It is to be understood that the present invention is not to ybe limited to the exact details of construction shown and described for obvious modifications will occur to persons skilled in the art.

What we claim is:

1. Apparatus for producing drug folds in sheet material comprising an elongated base, means extending along said base for moving sheet material with an edge overlapping said base, an elongated Hanging member on said base having an inclined plane with a vertical Hange-supporting shoulder of progressively increasing height, paper guiding means supported adjacent said shoulder for causing sheet material overlapping the inclined plane to be transferred to an upwardly Hanged position adjacent said shoulder, fixed means on said base and extending longitudinally thereof and positioned to be engaged by the upward Hange of said sheet for thereafter folding said Harige downwardly to product a doubled-over edge, fixed means on said base extending longitud-inally thereof and positioned to be engaged by said doubled-over edge for Hanging said doubled-over edge upwardly, and fixed means on said base extending longitudinally thereof for folding said last mentioned upwardly flanged portion downwardly.

2. Apparatus `for producing drug folds in sheet material comprising an elongated base, means extending along said base for moving sheet material with an edge overlapping said base, fixed means on said base extending longitudinally thereof and positioned to be engaged by said overlapping sheet edge for Hanging a portion of said edge upwardly, a down-folder having an overhang all in the same plane of progressively increasing width, guiding means supported so that a portion projects beneath said overhang and adjacent the fold line for said Hange of the sheet material to cause said Hange to be folded downwardly beneath the overhang and around said guiding means as the sheet travels, fixed means on said base extending longitudinally thereof and positioned to be engaged by said doubled-over edge for Hanging said doubled-over edge upwardly, fixed means on said base extending longitudinally thereof for folding said last mentioned upwardly Hanged portion downwardly and fixed means extending longitudinally of said base for compressing said fold.

3. Apparatus for producing drug folds in sheet material comprising an elongated base, means extending along said base for moving sheet material with an edge overlapping said base, Hxed means on said base extending longitudinally thereof and positioned to be engaged by said overlapping sheet edge for Hanging a portion of said edge upwardly, fixed means on said base and extending longitudinally thereof and positioned to be engaged by the upward Hange of said sheet for thereafter folding said flange downwardly to produce a doubled-over edge, fixed means on said base extending longitudinally thereof and positioned to be engaged by said doubled-over edge for Hanging said doubled-over edge upwardly, said fixed means including a longitudinal support shelf for the sheet material which is immediately adjacent said upwardly Hanged doubled-over edge, intermittently effective rotary means operable in timed relationship with said sheet moving means and positioned to apply adhesive to the sheet material from one side and adjacent said last upwardly Hanged portion while the portion of the said material `to which the adhesive is being applied is supported from its opposite side by said longitudinal support shelf, fixed means on said base extending longitudinally thereof for folding said last mentioned upwardly Hanged portion downwardly, and lmeans for compressing said fold to cause the adhesive to maintain the drug fold in position.

4. Apparatus for producing drug folds in sheet material comprising an elongated base, means extending along said base for moving sheet material with an edge 6 overlapping said base, an elongated Hanging member on said base having an inclined plane with a vertical Hangesupporting shoulder of progressively increasing height, paper guiding means supported adjacent said shoulder for causing sheet material overlapping the inclined' plane to be transferred to an upwardly Hanged position adjacent said shoulder, fixed means on said base and extending longitudinally thereof and positioned to be engaged by the upward Hange of said sheet for thereafter folding said Hange downwardly to produce a doubledover edge, fixed means on said base extending longitudinally thereof and positioned to be engaged by said doubled-over edge for Hanging said doubled-over edge upwardly, intermittently effective rotary means operable in timed relationship with said sheet moving means and positioned to apply adhesive to the sheet material adjacent said last upwardly Hanged portion, fixed means on said base extending longitudinally thereof for folding said last mentioned upwardly Hanged portion downwardly, and fixed means extendinglongitudinally of said base for compressing said fold to cause the adhesive to maintain the drug fold in position.

5. Apparatus for producing drug folds in sheet material comprising an elongated base, means adjacent said base for moving sheet material therealong with :an edge overlapping said base, an elongated Hanging member on said base having an inclined plane with a vertical Hange-supporting shoulder of progressively increasing height, paper guiding means supported adjacent said shoulder for causing sheet material overlapping the inclined plane to be transferred to an upwardly Hanged position adjacent said shoulder, a down-folder having an overhanging shoulder, guiding means supported so that a portion projects beneath said shoulder and adjacent the fold line for said Hange of the sheet material to cause said Hange to be folded downwardly beneath the shoulder and around said guiding means as the sheet travels, a second Hanging means having an inclined plane with a side shoulder, guiding means supported adjacent said inclined shoulder for causing said doubled down edge to be transferred from a position on said inclined plane to an upwardly Hanged position adjacent said shoulder, a second down folder having an overhanging shoulder, paper guiding means having a portion positioned beneath said shoulder for causing said upwardly Hanged portion to be transferred to a position beneath said shoulder and folded around said guiding means, and means for cornpressing said final fold.

6. Apparatus for producing drug folds in sheet material comprising an elongated base, means adjacent said base for moving sheet material therealong with an edge overlapping said base, an elongated Hanging member on said base having an inclined plane with a vertical Hangesupporting shoulder of progressively increasing height, upright paper guiding means supported adjacent said shoulder and spaced outwardly therefrom for causing sheet material overlapping the inclined plane to be transferred to an upwardly Hanged position between said shoulder and guiding means, a down-folder having an overhanging shoulder, guiding means supported so that a portion projects beneath said shoulder and adjacent the fold line for said iiange of the sheet material to` cause said Hange to be folded downwardly beneath the shoulder and around said guiding means as the sheet travels, a

second Hanging means having an inclined plane with a side shoulder, upright guiding means supported adjacent said inclined shoulder and spaced outwardly therefrom for causing said doubled down edge to be transferred from a position on said inclined plane to an upwardly Hanged position adjacent said shoulder, a second down-folder having an overhanging shoulder, paper guiding means having a portion positioned beneath said shoulder for causing said upwardly Hanged portion to be transferred to a position beneath said shoulder `and folded around said guiding means, and means for compressing said final fold.

7. Apparatus for producing drug folds in sheet material comprising7 an elongated base, means adjacent said base for movingr sheet material therealong with an edge overlapping said base, an elongated lianging member on said base having an inclined plane with a vertical ilangesupporting shoulder of progressively increasing height, upright paper guiding means supported adjacent said shoulder and spaced outwardly therefrom for causing sheet material overlapping the inclined plane to be transferred to an upwardly flanged position between said shoulder and guiding means, a down-folder having an overhanging shoulder of progressively increasing width, guiding means supported so lthat a portion projects beneath said shoulder and adjacent the fold `line for said flange of the sheet material to cause said ange to be folded downwardly beneath the shoulder and around said guiding means as the sheet travels, a second anging means having an inclined plane with a side shoulder, upright guiding means supported adjacent said inclined shoulder and spaced outwardly therefrom for causing said doubled down edge to be transferred from a position on said inclined plane to an upwardly flanged position adjacent said shoulder, a second down-folder having an overhanging shoulder of gradually increasing width, paper guiding means having a portion positioned beneath said shoulder for causing said upwardly anged portion to be transferred to a position beneath said shoulder and folded around said guiding means, and means for compressing said final fold.

8. Apparatus for producing drug folds in sheet material comprising an elongated base, means adjacent said base for moving sheet material therealong with an edge overlapping said base, an elongated hanging member on said base having an inclined plane with a vertical ange-supporting shoulder of progressively increasing height, paper guiding means supported adjacent said shoulder for causing sheet material overlapping the inclined plane to be transferred to an upwardly tianged position adjacent said shoulder, a down-folder having an overhanging shoulder, guiding means supported so that a portion projects beneath said shoulder and adjacent the fold line for said ange of the sheet material to cause said flange to be folded downwardly beneath the shoulder and around said guiding means as the sheet travels, a second anging means having an inclined plane with a side shoulder, guiding means supported adjacent said inclined shoulder for causing said doubled down edge to be transferred from a position on said inclined plane to an upwardly flanged position adjacent said shoulder, means for applying an adhesive to the sheet material adjacent said shoulder, a second down-folder having an overhanging shoulder, paper guiding means having a portion positioned beneath said shoulder for causing said upwardly anged portion to be transferred to a position beneath said shoulder and folded around said guiding means, and means for compressing said inal fold.

9. In an apparatus for producing folded edges in sheet material, said apparatus having an elongated base and having means adjacent said base for moving sheet material therealong with an edge overlapping said base, a solid flanging member having an upwardly facing inclined sheet edge receiving plane with a vertical flange-supporting shoulder of progressively increasing height, paper guiding means supported adjacent said shoulder for causing sheet material overlapping the inclined plane to be transferred to an upwardly flanged position adjacent said shoulder, and means for thereafter folding said flange downwardly into parallelism with the sheet.

10. In an apparatus for producing folded edges in sheet material, said apparatus having an elongated base, and having means adjacent said base for moving sheet material therealong with an edge overlapping said base, means cacting with said base for causing sheet material overlapping the base to be folded to an upwardly anged position,

a down folder of solid bar stock having an upright shoulder and having an overhanging shoulder all in the same plane projecting laterally from an upper portion of said upright shoulder and of a width progressively increasing from zero, and guiding means having a portion projecting beneath said overhanging shoulder and adjacent the fold line for said ange adjacent said upright shoulder to be engaged by said progressively increasing overhanging shoulder and to cause said yiiange to be folded downwardly beneath the shoulder and around said guiding means as the sheet travels.

11. 1n an apparatus for producing folded edges in sheet material, said apparatus having an elongated hase, and having means adjacent said base for moving sheet material therealong with an edge overlapping said base, means coacting with said base for causing sheet material overlapping the base to be folded to an upwardly flanged position, a down-folder having an overhanging shoulder of gradually increasing width, paper guiding means having a vertical portion positioned adjacent the side of said shoulder and having an inwardly rolled portion of progressively increasing width projecting beneath said shoulder for causing said upwardly anged portion to be transferred to a position beneath said shoulder and folded around said guiding means, and means for compressing said nal fold.

12. In an apparatus for producing folded edges in sheet material, said apparatus having an elongated base, and having means adjacent said base for moving sheet material therealong with an edge overlapping said base, means coacting with said base for causing sheet material overlapping the base to be folded to an upwardly flanged position, means for applying an adhesive to the sheet material adjacent said ange, a down-folder having an overhanging shoulder of gradually increasing width, paper guiding means having a vertical portion positioned adjacent the side of said shoulder and having an inwardly rolled portion of progressively increasing width projecting beneath said shoulder for causing said upwardly flanged portion to be transferred to a position beneath said shoulder and folded around said guiding means, and means for compressing said nal fold.

13. In an apparatus for producing folded edges in sheet material, said apparatus having an elongated base, and having means adjacent said base for moving sheet material therealong with an edge overlapping said base, means coacting with said base for causing sheet material overlapping the base to be folded to an upwardly anged position, a down folder having an overhang of progressively increasing width for folding said flange downwardly, and creasing means below the sheet material yieldingly pressing said flange from below against said overhang to crease the ange in downfolded condition.

14. In an apparatus for producing folded edges in sheet material, said apparatus having an elongated base, and having means adjacent said base for moving sheet material therealong with an edge overlapping said base, means coacting with said base for causing sheet material overlapping the base to be folded to an upwardly flanged position, a down folder having an overhang for folding said ange downwardly, and creasing means below the sheet material yieldingly pressing said flange from below against said overhang to crease the ilange in downfolded condition.

References Cited in the file of this patent UNITED STATES PATENTS 1,341,832 Avery et al. lune 1, 1920 1,439,850 Teeple Dec. 26, 1922 2,245,348 Laver June l0, 1941 2,265,894 Caldes Dec. 9, 1941 2,331,067 Young Oct. 5, 1943 2,441,445 Ringler et al May 11, 1948 2,772,088 Nelson Nov, 27, 1956 

